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Introgressive hybridization between wolves and dogs is a conservation concern due to its potentially deleterious long-term evolutionary consequences. European legislation requires that wolf-dog hybridization be mitigated through effective management. We developed an individual-based model (IBM) to simulate the life cycle of gray wolves that incorporates aspects of wolf sociality that affect hybridization rates (e.g., the dissolution of packs after the death of one/both breeders) with the goal of informing decision-making on management of wolf-dog hybridization. We applied our model by projecting hybridization dynamics in a local wolf population under different mate choice and immigration scenarios and contrasted results of removal of admixed individuals with their sterilization and release. In several scenarios, lack of management led to complete admixture, whereas reactive management interventions effectively reduced admixture in wolf populations. Management effectiveness, however, strongly depended on mate choice and number and admixture level of individuals immigrating into the wolf population. The inclusion of anthropogenic mortality affecting parental and admixed individuals (e.g., poaching) increased the probability of pack dissolution and thus increased the probability of interbreeding with dogs or admixed individuals and boosted hybridization and introgression rates in all simulation scenarios. Recognizing the necessity of additional model refinements (appropriate parameterization, thorough sensitivity analyses, and robust model validation) to generate management recommendations applicable in real-world scenarios, we maintain confidence in our model's potential as a valuable conservation tool that can be applied to diverse situations and species facing similar threats., (© 2024 The Author(s). Conservation Biology published by Wiley Periodicals LLC on behalf of Society for Conservation Biology.)

We previously reported that proline modulates root meristem size in Arabidopsis by controlling the ratio between cell division and cell differentiation. Here, we show that proline metabolism affects the levels of superoxide anion (O 2 •- ) and hydrogen peroxide (H 2 O 2 ), which, in turn, modulate root meristem size and root elongation. We found that hydrogen peroxide plays a major role in proline-mediated root elongation, and its effects largely overlap those induced by proline, influencing root meristem size, root elongation, and cell cycle. Though a combination of genetic and pharmacological evidence, we showed that the short-root phenotype of the proline-deficient p5cs1 p5cs2/P5CS2 , an Arabidopsis mutant homozygous for p5cs1 and heterozygous for p5cs2 , is caused by H 2 O 2 accumulation and is fully rescued by an effective H 2 O 2 scavenger. Furthermore, by studying Arabidopsis mutants devoid of ProDH activity, we disclosed the essential role of this enzyme in the modulation of root meristem size as the main enzyme responsible for H 2 O 2 production during proline degradation. Proline itself, on the contrary, may not be able to directly control the levels of H 2 O 2 , although it seems able to enhance the enzymatic activity of catalase (CAT) and ascorbate peroxidase (APX), the two most effective scavengers of H 2 O 2 in plant cells. We propose a model in which proline metabolism participates in a delicate antioxidant network to balance H 2 O 2 formation and degradation and fine-tune root meristem size in Arabidopsis .

Introduction: Cushing's disease (CD) is a rare and severe endocrine disease characterized by hypercortisolemia. Previous studies have found structural brain alterations in remitted CD patients compared to healthy controls, specifically in the anterior cingulate cortex (ACC). However, potential mechanisms through which these persistent alterations may have occurred are currently unknown., Methods: Structural 3T MRI's from 25 remitted CD patients were linked with gene expression data from neurotypical donors, derived from the Allen Human Brain Atlas. Differences in gene expression between the ACC and an unaffected control cortical region were examined, followed by a Gene Ontology (GO) enrichment analysis. A cell type enrichment analysis was conducted on the differentially expressed genes, and a disease association enrichment analysis was conducted to determine possible associations between differentially expressed genes and specific diseases. Subsequently, cortisol sensitivity of these genes in existing datasets was examined., Results: The gene expression analysis identified 300 differentially expressed genes in the ACC compared to the cortical control region. GO analyses found underexpressed genes to represent immune function. The cell type specificity analysis indicated that underexpressed genes were enriched for deactivated microglia and oligodendrocytes. Neither significant associations with diseases, nor evidence of cortisol sensitivity with the differentially expressed genes were found., Discussion: Underexpressed genes in the ACC, the area vulnerable to permanent changes in remitted CD patients, were often associated with immune functioning. The specific lack of deactivated microglia and oligodendrocytes implicates protective effects of these cell types against the long-term effects of cortisol overexposure., (Copyright © 2021 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Social withdrawal is an early and common feature of psychiatric disorders. Hypothalamic-pituitary-adrenal (HPA)-axis activation through increased salivary cortisol (sC) and sympathetic activation through increased salivary alpha-amylase (sAA) may play a role. We aimed to study whether the link between increased sC and sAA on the one hand and depression on the other hand is mediated by social withdrawal. In this cross-sectional, observational study, sC and sAA measures were measured in seven saliva samples in 843 participants (231 psychiatric patients and 612 healthy controls). Social withdrawal was assessed through the Brief Symptom Inventory (BSI)-, the Short Form 36-, and the Dutch Dimensional Assessment of Personality Pathology social withdrawal subscales, and analyzed using linear regression and mediation analyses. On average, participants were 44.0 years old (SD = 12.8; 64.1% female). Basal and diurnal sAA were unrelated to any social withdrawal scale and depression. Certain sC measures were positively associated with the BSI social withdrawal subscale (i.e., area under the curve with respect to the increase, beta = 0.082, p = 0.02; evening sC value: beta = 0.110, p = 0.003; and mean sC value: beta = 0.097; p = 0.01). We found limited support for statistical mediation by social withdrawal (measured using a composite social withdrawal score) on the relationship between evening sC and depression. Thus, although we found no support for a role of basal and diurnal sAA in social withdrawal, HPA-axis activation may partly aggravate social withdrawal in depressive disorders., (Copyright © 2020 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Land-use change and climate change are recognized as two main drivers of the current biodiversity decline. Protected areas help safeguard the landscape from additional anthropogenic disturbances and, when properly designed, can help species cope with climate change impacts. When designed to protect the regional biodiversity rather than to conserve focal species or landscape elements, protected areas need to cover a representative sample of the regional biodiversity and be functionally connected, facilitating individual movements among protected areas in a network to maximize their effectiveness. We developed a methodology to define effective protected areas to implement in a regional network using ecological representativeness and functional connectivity as criteria. We illustrated this methodology in the Gaspésie region of Québec, Canada. We simulated movements for the endangered Atlantic-Gaspésie caribou population (Rangifer tarandus caribou), using an individual-based model, to determine functional connectivity based on this large mammal. We created multiple protected areas network scenarios and evaluated their ecological representativeness and functional connectivity for the current and future conditions. We selected a subset of the most effective network scenarios and extracted the protected areas included in them. There was a tradeoff between ecological representativeness and functional connectivity for the created networks. Only a few protected areas among those available were repeatedly chosen in the most effective networks. Protected areas maximizing both ecological representativeness and functional connectivity represented suitable areas to implement in an effective protected areas network. These areas ensured that a representative sample of the regional biodiversity was covered by the network, as well as maximizing the movement over time between and inside the protected areas for the focal population., Competing Interests: The authors have declared that no competing interests exist.

Future human land use and climate change may disrupt movement behaviors of terrestrial animals, thereby altering the ability of individuals to move across a landscape. Some of the expected changes result from processes whose effects will be difficult to alter, such as global climate change. We present a novel framework in which we use models to (1) identify the ecological changes from these difficult-to-alter processes, as well as (2) the potential conservation measures that are best able to compensate for these changes. We illustrated this framework with the case of an endangered caribou population in Québec, Canada. We coupled a spatially explicit individual-based movement model with a range of landscape scenarios to assess the impacts of varying degrees of climate change, and the ability of conservation actions to compensate for such impacts on caribou movement behaviors. We found that (1) climate change impacts reduced movement potential, and that (2) the complete restoration of secondary roads inside protected areas was able to fully offset this reduction, suggesting that road restoration would be an effective compensatory conservation action. By evaluating conservation actions via landscape use simulated by an individual-based model, we were able to identify compensatory conservation options for an endangered species facing climate change.

Background: Specific Major Depressive Disorder (MDD) biomarkers could help improve our understanding of MDD pathophysiology and aid in the refinement of current MDD criteria. While salivary cortisol (SC) can differentiate between healthy controls and patients with psychiatric disorders, salivary alpha amylase (sAA), may be a putative candidate biomarker for MDD specifically., Methods: In a naturalistic cohort of consecutive out-patients and healthy controls, sAA and SC were determined in 833 participants (97 MDD patients, 142 patients with other mood, anxiety, and/or somatoform (MAS-) disorders, and 594 healthy controls). Samples were collected at 7 different time points (at awakening, after 30, 45, and 60 min, at 10:00 p.m., at 11:00 p.m., and at awakening on day 2)., Results: The mean age of the sample was 43.8 years (SD = 12.9; 63.9% female). Concerning sAA, MDD patients had higher sAA levels upon awakening on two consecutive days (p = 0.04, p = 0.01 respectively), as well as a higher area under the curve with respect to the increase (AUCi; p = 0.04) in comparison to both controls and the other MAS-disorders group. Regarding SC, mean levels of evening SC were elevated in MDD patients (p = 0.049) in comparison to both controls and the other MAS-disorders group. SC values on day 2 after ingestion of dexamethasone were elevated in both MDD patients and the other MAS-disorders group (p = 0.04, p = 0.047 respectively)., Conclusions: sAA at awakening and not cortisol differentiates MDD from other psychiatric disorders in outpatients. This suggests that sAA may be a valuable candidate biomarker specifically for MDD., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

This corrects the article DOI: 10.1038/nature22974.

Aerosols have a potentially large effect on climate, particularly through their interactions with clouds, but the magnitude of this effect is highly uncertain. Large volcanic eruptions produce sulfur dioxide, which in turn produces aerosols; these eruptions thus represent a natural experiment through which to quantify aerosol-cloud interactions. Here we show that the massive 2014-2015 fissure eruption in Holuhraun, Iceland, reduced the size of liquid cloud droplets-consistent with expectations-but had no discernible effect on other cloud properties. The reduction in droplet size led to cloud brightening and global-mean radiative forcing of around -0.2 watts per square metre for September to October 2014. Changes in cloud amount or cloud liquid water path, however, were undetectable, indicating that these indirect effects, and cloud systems in general, are well buffered against aerosol changes. This result will reduce uncertainties in future climate projections, because we are now able to reject results from climate models with an excessive liquid-water-path response.

The efficacy of a sustained released granular formulation of Bacillus sphaericus strain 2362 was compared to a flowable concentrate in containers, cesspools, and water ponds. Duration of control was dependent on formulation, dosage, exposure to sun, site, recycling, and target mosquito larvae. In a series of container tests with repeated additions of fourth-instar Culex quinquefasciatus larvae exposed to 0.3 or 3.0 g/m2 when cadavers were not removed, more than 95 percent control was obtained for two and four days in containers that were exposed to the sun with sewage water treated with the flowable concentrate compared to four and seven days for those treated with the granule. In sun-exposed containers with sewage water, control persisted for two days for the flowable concentrate at both dosages and one and six days for the granule at 0.3 g/m2 and 3.0 g/m2, respectively. Compared to the above tests, more than seven weeks control was obtained with 0.3 g/m2 of the flowable concentrate in closed containers where larvae were added weekly. In closed containers without weekly addition of larvae, the control was 15 percent when larvae were added five weeks after the treatment. Spore counts at the surface and bottom of the containers with lids showed an increase in number of spores at the surface where larvae were added weekly and a rapid decline where they were not. Spore counts at the bottom showed settling in both cases, but to a much higher level where larvae were added weekly. Nearly 100 percent control of Cx, quinquefasciatus larvae was obtained for at least 16 days in cesspools in Yaoundé, Cameroon, treated with the granule at 3.0 g/m2 compared to approximately nine days for the flowable concentrate. At 0.3 g/m2, the duration of this reduction was five days for both products. Nearly 100 percent control of Anopheles gambiae was obtained in sun-exposed water ponds near the village Kotiokh, Senegal, for at least 15 days with the granule at 3.0 g/m2 compared to just five days for the flowable concentrate at the same dosage.